Improvement in processes of separafing metals



0. WIEGAND. Process of Separating Metals.

No.196,848. Patented Nov. 1877.

NVPETERS, PHOTD-LITNOGRAPHER, WISHINGTON. D C.

P OFFI E corneal) WIEGAND, OF VIRGINIA CITY, EVADA;

IM PROVEM E'NT IN PRoCEssize ioF sEPARAiFi'N'G METAL Specification forming m of Letters Patent No. 196,848, dated Novemberfi, 157,7; applicationfiled;

July 28,1876., 7

To all-whom it may-'conccrnr y Be it known that I, 001mm) WLEGAND, of Virginia City, Storey county, Nevada, haveinventedan Improved Method or Process for Separating Metals, or the amalgams of metals,

from each other; and I hereby declare the following. description, with, reference to accompanying drawings, to be sufficient to enable any person skilled in the art to which it most nearly appe'rtains to understand and use my said invention, and to avoid an unwitting invasion or infringement of my rightstherein or thereun-to appertaining; t

c The method herein described is necessarily a complement of fan allied or somewhat similar process for the mercurial separation of silver from'other' metals, for which process Letters Patent No. 145,265 wereissued by the United States to me December 2, 1873, and reissued as 5,934, June 23, 1874. That process can scarcely be successfully operated without a simultaneous action or conductof the process herein described; nor can either process be plainly described without the use of so many terms and phrases. which are similar that a description of either process must be compared closely-with that of the other to note the diflerences. In like manner, the apparatus herein described embraces among novelties certain features which havebeen described in the above-recited patent and reissue, or in Letters Patent of the United States issuedto me October 11, 1875, and numbered #168,695, the same being for'a process byfwh-ich to separate gold from other metals.

The process herein described-embracesthe following steps:. I, i. First, the amalgamation of the'metals which are to be separated from each other, and thinning: the amalgams to a point of free mobility of particles among themselves, by using an excess ofquicksilver as, a solvent, without'or with heat, howsoever applied, with or without trituration or agitation, and with or without the addition of other metalsor amalgams having a molecular tendency to the disintegra- .tion, solution, or mechanical suspensionin quicksilver of the amalgamated metals which are to be separated" from each other; also, ,in maintaining free mobility of the ,particles' among each otherin quicksilver, either by i i rat am J1 or y swe tener-tee 5 otherwise introducing quicksilver ("cold oiihot) into the vesselmutainingttefilfifihtd" amalgam, or, by any combination of these re- 1 sorts with each other,havingforitsiobject the separation of the I amalgams from each other. Second, whenithe difieringspecific grain, ties of the amalgamated metals which are to; be separated do not lead to a gravit if i've. sepa ration by flotation and subsidence+the lighter amalgams floating, while those denserfthaii quicksilver sinkt1iemaint'ainii1'g of a regulated, current or circulation of quicksilver within and through the vessel containing the thinned amalgams. Q' I, Third, the col1ection '(by straining, b'y'crya tallization, or by deposition) offsiich portions of amalgam, as may separate byflotation or subsidence, or of such portions as m y be separated fromeach other by the current or quicksilver above slluded to. v 4 Fourth,retorting the separated a algam, that the metals contained may be melted;

The process, above summarily described can be made plain in its operation morereadily a properly-described diagram of the apparatus adapted to it thanby other means. i

Diagram No.2 represents a very simple of apparatus adapted to the separation of nished with a ,valve similar to an .uoi'dine I stovepipe damper or a butterfly valve,tuii1- ing on an axiseshaft, a, inits middle.

, vH represents a ha dle, by which it turned from the outside: Theaxis 'shaft (1 passes througha stuffing boms b, designed'to make a quicksilver-tight join V I ,t B and C.representlstoppocks, throu h which .amal'gams after a ravitati've separationjhas aken 19 m A l.- v 1 1 t I When-,thevalve Vis edge up, itis plain that if highly fiuid mixed amalgams ar piaceu inthe vessel S, and that if it then be filled ,u'p

with-quicksilver, the amalgains which. are,

lighter than quicksilver will float to thetop of compartment U, while ,thosewhich are denser will sink to the bottom of compartto drawoff the quicksilver and suspen e me'nt II. The separation having been efifected, the valve-V may be closed and the contents of U drawn off through 0 and strained. Afterward the contents of L, drawn off through B, may also be strained.

In practice, the above form of apparatus is less generally useful thanthat represented in Diagram No. 1. The reason is, but few amalmixed amalgams be fed in at the bottom of a vessel charged with quicksilver, almost all of them would float upward. The specifically lightest would rise most rapidly, and at the surface they would be found measurably arranged in zones, layers, or tires. Copper amalgain, for instance, is specifically lighter than silver amalgam, yet when neither is crystallized both are lighter than quicksilver. Both, therefore, when not afi'ected by crystallization, rise in quiescent quicksilver.

The upward motion of copper" amalgam might be'denotcd by ten units per minute.

Theflotative tendency (or upward motion in quiescent quicksilver) of silver amalgam should then be denoted by about two units per minute, In quiescent quicksilver, therefore, time and opportunity afl'orded, copper amalgam will ride higherthan silver amalgam in a separating-vessel containing quicksilver. In such a vessel as that shown by DiagramNo. 2 both would be found in compartment'U. Such a vessehtherefore, could not eifect a perfect scarcely a usefi11separation' of copper and silver amalgams. But it is obvious that if, while both the copper and silver amalgams are rising with respective speeds, ten and two, theyshould be compelled to rise through sinking quicksilver-that is, through a slow downward current of quicksilver-in stead of throu gh standing quicksilver; and if the downward current or sinking of the quicksilver be five units per minute, the net upward motion of the copper a amalgam in the vessel wouldbe reduced from ten to five, while the upward motion of the silver amalgam would be entirely overcome, and it would be carried out of the vessel in the current witha speed of three degrees per minute, and thereby be sep arated from the copper amalgam. v v

To efl'ect a separation of fluid amalgams, therefore, provided their specific gravities differfrom each other, it is only needful to submerge them in a slow current of quicksilver. If both amalgams are lighter than quicksilver,

or if one is lighter and the other is heavier or denser, thecurrent should be directed downward. l If both are denser than quicksilver, the

current should be directed upward, as will more fully appear hereinafter.

The downward current should be speeded at a less rate than the fiotative speed of the lighter algam, :while i at the same time at a greater speed than the flotative speed of the denser. When an up-' ward currentis necessary, it should be speeded at a greater rate than the subsiding tendency of the less dense amalgam, but at a slower.- rate than the subsidingtendency of the denser 'amalgam. I i I An apparatus designedboth to create and regulate these currents, and to control them No. 1 herewith.

D represents an upright vessel, which may be termed the digester Its sides are im- 1 pervious to quicksilver-epreferably of iron,

smoothed insideand furnishedwith a movaf ble lid, L, bottom B, and gatej opening sidewise.

1 Between the lower end of the digesterand bot tom B aperforated ironplate, p, is represented,

the joint being made quicksilver-tight,as is I morefully described and represented inthe pat- 1 e This plate does not arrest the passage of quicksilverfor of I amalgam in chemical solution, or of amalgam finely comminuted; but it does. prevent any e In thisre? ents hereinbefore referred to.

lumps of amalgam finding spect it operates as do the egress.

meshes of a straining-clothwheninsertedatthispoint. Provided i the amalgams to be separated arelighter than quicksilver, maintained in the digester,

or perforated'screen or plate is necess though in general it is desirable.

if a large excess of quicksilver "is Both the digester D nd the b a-om should be furnished with jackets} J J, J, designedto, heat and cool by. Water orsteam, of regulatcd temperature, or hotairf or oiladmitted therein and caused to circulate throughwthe pipe 81'; and exhausting through the exhaust} pipes e1) and e 1), willheat the digester, and, he

when desired, a current of cold waterwill cool it. v Through the gate G the residuary amalgam,

after a separation has beenfefiected, maybe For the same purpose, when found moreconvenient, a draw-ofl' pipe,d 0, may bdi inserted in or near thebottom of the digester, through which, aided by the agitator am ss" removed.

represented, and assisted bya showeror stream of quicksilver, as providedfor by the elevator E E, &c., the residuary amalgam may befin 1 good part, washed out, withoutF-openingthe side gate Gr.

may pass. (See an.)

. Beneath the lid it is 'a rim is raised to form a central colander,c

0, so that quicksilver, when fed in at that poi nt,

be put therein to be dissolved by the stream of hot quicksilver which may be fed in there.

The digester should also be furnished with in either direction, is represented in diagram no straining-cloth; 1 r lfe v The M Shofild o jfurnishdwitl a g-D X, 87), through '\vhi h:t h fbwon spindle of a revolving and adj a y e V desirable tointrod uce a perforated iron plate, in the middle of; which a top feed, tf, a bottomfeed, I; f, and an under feed, ufyalso with a feed-pipe, f 1a,for feeding in dissolved amalgam at the bottom, anda stand-pipe or gage-pipe, g1), designed to carry a float, which can be made to'show the level of the quicksilver and amalgam in the digester. This pipe should beattached to the quicksilver-pipe q p, in sucha way that the inward flow of quicksilver to the digester across the foot of the pipe will prevent amalgam backing fromthe digesteiywhich would (16;:

range the indications of the float byclogging thepipegp.

' As an adjunct for heating,thefeeding-quicka pipe'bearing the main stop-cock M O, by

which the flow of quicksilver from the digester can be arrested without deranging speed-ad;

justments elsewhere. Besides this main cock, on branches of the same pipe are two smaller stop-cocks. One, 8,0, is a sampling-cock, de'- signed to draw off a sample of what is passing with the quicksilver to the cooler, so that the nature, quantity, and'quality of amalgam passing at any moment may be determined without arresting the operation of the apparatus. This c'ock may be located elsewhere than as represented in the diagram. The'other small cock r c is the regulating-cock, by means of which the downward speed of quicksilver in the digester may be controlled; This stop"- 7 cock delivers quicksilver to an iron cooler, O.

The cooler C is an iron tank. Ribs or partial' partitions 1' 1' r 73in Figs. 1 and-2, and which run part way across the cooler, are set on -the upper side of its bottom, so that the quicksilver running from 'r' 0 into the cooler at I must traverse the cold-iron surface before finding outlet at 0, Figs. 1 and 2."

Water confined by the partition'Pitself furnished with a trap, q t'-covers at least a portion of the cooler-surface. The intention of confining this water is to prevent fumes of I mercury rising in the air. It is discharged hot beneath the surface of the water, whose temperature is kept low.

On the under side of the cooler w w cold water is made to circulate, sothat after passing through the cooler the quicksilver from r a, bearing in or with it amalgam, is ready to be strained in the sack or collector K.v The amalgam remains in the sack, and the quick- By the foregoing appliances the circulation of quicksilver is continued at a duly-regulatedspeed, and at proper points of inflow,untilthe desired separation of amalgams is completed,-

or till carried to a point at which a'furthe'r separation ceases to be profitable.

- The. prompt separation of amalgams depends largely upon comminution of the mixed amalgams. The simplest method for this is to grind cold, with a-covering of water in an amalgamating pan. I The addition of a small amount of sodium, or of sodium amalgam, or of zinc amalgam while grinding is-helpful when the amalgams to be separated have formed themselves into hard cakes. When ground fine, it

should be diluted-with quicksilver, and' fed into the digester as soon as possible after igrindingfln order to avoid the reformation of cakes and crystals. For ordinaryworking, before amalgam is introduced the: digester should be charged with heated quicksilver.

* S F, in Diagram No. 1, represent an iron ,(or

an iron-covered) floor, shedding toward. and vemptyinginto a safety-tank, S T, and more particularly described in the patents hereinbefore referred to.

Fig. 3, in Diagram-No. 1,- represents atop view of the cooler G; and q t, inFigs. land 2, represent the quicksilver-trap for water, through which quicksilver flows freely, but wa ter cannot, because buoyed away by the quicksilver from the aperture. 10 i represent the Water-inflow beneath the bottom of the cooler. r r, r 1* represent ribs on the under side of the cooler-bottom Y .Y, which, in' connection with the under lid u 1, form a Water-channel,

and compel the v cooling-water to move under the entire surface of the cooler-bottom. o is the outflow of the spout or pipe through-which the cooled quicksilver is delivered to the col-- lector-tank KT, which tank is made capacious to guard against accidents or breakage in the 1 apparatus above it. I

- Several straining-sacks or collectors may be attached to the same collector-tank to. avoid delay in cleaningv up. Common wooden plugs are sufiicient to arrest the'flow of quicksilver into any collect0r.-

, FlgS;.3"a,l1d4-, Diagram No. 1, represent 1 and side views. of the heating-box'H-B forheating quicksilver on its way to the digester.

The partition between the quicksilver-compartment' q q and} the steam-chamber s s is marked-P. The'upper lid is marked -L', and the lower lid L. The quicksilver-channel, as

also the steam-chamber, is formed by bolting the upper and lower lids to each'other and rarer, the bottom feed of. the digester is chiefly used. When the separation of amalgams, both of which are lighter than quicksilver, is aimed at, the top feed must chiefly be used,

enough being fed in at the bottom to prevent a failure of indications on the gage piper When it is designed 'to separate amalgams whose specific gravitiesare both greater spe cific gravity than that of quicksilver, but which differ from each other, an upwardwcux'rent 'of quicksilver must be provided; Thisnpwaid current is secured by causing the quicksilver to flow in by the pipe u 1f,(u11der feed,) qthe main cock having been previously closed: The

outflow in this case is by the pipe which congects with the air-pipe a p and disehargepipe it 1 =1 a 1" The lighter amalgam havingbee'n borne off" in the upwardcufrrent, the remaining dense amalgam may be taken from the digester in either of two ways. One is to out oil? the in flow of quicksilver, and their speed theagitator a a sufficiently todiflhse the remaining amal gamthroughout the'quicksilver. Thateffected, communicationis opened to the base collectortank K T by opening a stop-cock in the drawofi pipe d 0 The contents of the digester will thereupon vent themselves to the collector, where the quicksilver will strain off and leave the amalgam in K. i t i i i 'The other methodis admissible whenthe digester-bottom is furnished'with a (screen,- as I described; In that caseyafter cutting on the inflowof quicksilver, open themain cock and allow the excess of quicksilver to drain through the digester-bottom to; the'coolerGz When drained,- the gate-G is opened and the amalgam removed. The same course is pursued, also, whenlighter amalgams have been stripped of denser ones by a downward current; i I i The process, as described inthis paper, is largely mechanical, and'as such, to a certain extent,-it can be carried on cold; but as heating in quicksilver causes amalgam to' dissolve into itsultimate molecules morerapidl'y than it will cold, thereby'efi'ecting separation, heating is recommended for practicalworb ing. As agitation also 'expedites prompt solution, an initial agitation is also commended, of a brisk character, as also a continuous but gentle agitation of the amalgams at the top of the digester. Both of these resorts will be greatly aided by a preliminary trituration of lumps and crystals, whether by'a pestle in i a mortar, or bygrinding in a pan or :milhorby any other resort having the aim of comminit tioninview.

mass

;protection. a Having E apparatus, and sufficiently theiproper proced-l for op secure by Letters Patent, is-

2. a The process 1 of 1 aidin 'gkthe through these amalgam mixed with quick,

silver to quick fluidity: and free mobility: of particles among themselves, asregulated cons tiiiuous downward. current of quicksilver,- the velocity of which: is. greater than the; rising tendency of the heavier amalgams, andat the, same time less? than that of itheiili'ghter gams, substantially as set forth: 1 u i a f3. Theprocess fo 'keepingathe standqiipe free from amalgam, uwhich consists in causing a part of the-feeding-stream of mercuryitosflow continuously beneath. its foot to: the digester, substantially aslherein set :fort-hl: 1 i a a a 4. The apparatus for operating the dynamic form of the process,- consisting, essentially, of the dig ester-D, :provided witlrthe gate and perforated plate p, and furnished with the combinationwith the revolvin gland adj ustable agitator ava colanderz 01c, feed-pipes :t j, b lfi u f,and f 11, gage-pipe gjz, quicksilver pipeq p, heating boxes H B, feeding-tankcj t, cooler O, and partition: 1?, provided Miththfiqtlfll); q

asdeseribed'.

In witnessiwhereof I have handandseali 1 m "n GONRAD WIEGAND; [LFSLJM Witnessesm" i l 1 The trituration of amalgam, in oi'der-rto cleanse it of dirt, iron, and other non ama k E. Q.'BUCKINGHAM, I i i 1 i SLiMQOREs' u gamable adhesions and foreign; matters, is not; znew,and I do'not claim thatapplication of itrituration or grinding but the imechanical 1;

comminution Y of amalgam by whateverineans, ias 'a preparation fora speedy sol'utionofamel gain in mercury, as related ptolthemercurioll y i separation of amalgam, is anovel application; Of grinding or triturationnfor which I (clain l thus described my process and my eration, what Lclaim and desire to li The process ofiseparatlngvmixed amalgamsv of "difi'erent A 1 specific 1 gravities, as herein @1 described, which consistswimpassing t, all constructed and arranged substantially fi sts-511558 1155? 

